Snap switch



Nov. 24, 1953 A. J. VAKSVIK 2,660,633

SNAP SWITCH Filed Jan. 4, 1951 4 Sheets-Sheet l fmuwyw Adm an J Yak-5122Nov. 24, 1953 A. J. VAKS\;IK 2,660,633

SNAP SWITCH Filed Jan. 4, 1951 4 Sheets-Sheet 2 INSULATION Admin J:vsksvzk Nov. 24, 1953 A. J. VAKSVIK SNAP SWITCH 4 Sheets-Sheet 3 FiledJan. 4, 1951 LI N EAR CLOSING MOTION OPENING MOTION Nov. 24, 1953 A. J.VAKSVIK 2,660,633

SNAP SWITCH Filed Jan. 4, 1951 4 Sheets-Sheet 4 mmmm: mm H .Adwzanmks-mk- Patented Nov. 24, 1953 SNAP SWITCH Adrian J. Vaksvik, Elkhart,Ind., assignor to Chicago Telephone Supply Corporation, Elkhart,

Ind., a corporation of Indiana Application January 4, 1951, Serial No.204,32ii

16 Claims.

This invention relates to electrical control devices such as combinedswitches and rlieostats, and refers more particularly to improvements inswitch mechanisms for such devices.

While combination electrical controls of this nature have many uses,their compactness makes them particularly well suited for use in smallradio receivers for controlling both the power supply and volume from asingle operating shaft.

One of the main objectives of this invention, however, is to provide acontrol instrumentality of the character described with a switchespecially designed for use with automobile radio receivers. Thesereceivers are supplied with power from the storage battery of theautomobile, which provides a low voltage source capable of accommodatingheavy power loads; and the. power switches for such receivers thus mustbe built for low voltage, high current service.

Conditions peculiar to such service are that the power switch can beeasily subjected to heavy overload current by a momentary short acrossthe storage battery during installation or servicing.

Consequently, the switch of this invention is provided with heavy lowresistance contacts capable of withstanding heavy overloads; and it isanother objective of this invention to provide the switch with operatingmechanism by which substantially uniform. low resistance contactpressure of a high order is maintained whenever the switch is closed.

Since more and more of the later model automobiles are being equippedwith instruments having lights controlled by a rheostat to enableregulation of the brightness of the instrument lights, it is also anobject to provide the switch of this invention with a second set ofcooperating stationary and movable contacts for governing operation ofthe pilot light of the radio receiver, to enable the pilot light to beconnected in the circuit controlled by the rheostat for the otherinstrument lights. This, of course, introduces other problems whichchiefly concern the maintenance of constant low resistance across twosets of stationary contacts in the switch in its closed position, and itis a further object of this invention to provide an improved double polesingle throw switch mechanism particularly suited for use with smallautomobile radio receivers, and which assures an adequate balancedcontact pressure between the movable contacts and their cooperatingstationary contacts in the closed position of the switch, to thusachieve minimum resistance in the two switch circuits at all times.

Still another object of this invention resides in the provision of asimplified snap switch having a contact carrier substantially looselyreceived in the switch casing and self-aligning with respect to thestationary switch contacts.

Another object of this invention resides in the provision or" animproved single throw double pole snap switch of the character describedvherein the contact carrier has its movable con tacts connected theretoat opposite sides of the 'riving connection between the carrier and themeans for snapping the same to its switch closed position so as toassure equalization of pressure between the movable contacts and theircooperating stationary contacts in the switch-closed position.

A further object of this invention resides in the provision of animproved and simplified manner of snapping the contact carrier to andfrom its switch-closing position.

With the above and other objects in view, which will appear as thedescription proceeds, this invention resides in the novel constructionand arrangement of parts substantially as hereinafter described, andmore particularly defined by the appended claims, it being understoodthat such changes in the precise embodiment of the hereinafter disclosedinvention may be made as come within the scope of the claims.

The accompanying drawings illustrate two complete examples of thephysical embodiments of the invention constructed in accordance with thebest modes so far devised for the practical application of theprinciples thereof, and in which:

Figure 1 is a view partly in side elevation and partly in sectionillustrating combined switch and rheostat embodying one form of thisinvention;

Figure 2 is a cross sectional view taken through Figure 1 along theplane of the line 22 with portions of the rheostat housing broken awayto show the mechanism inside the switch housing, and with the switch inopen position;

Figure 3 is a view similar to Figure 2 looking into the open end or" theswitch housing but showing no part of the rheostat housing, andillustrating the switch in closed position;

Figure d is a cross sectional view through Figure 1 taken along theplane of the line ii and showing the switch mechanism from the closedend of the switch housing, with the switch in open position;

Figure 5 is a cross sectional view taken through Figure 2 along theplane of the line 5--ii;

Figure 6 is a group perspective view showing the contact carrier andcontacts thereon, and the switch casing, but with these parts separated;portions of the side Wall of the switch casing being broken away toillustrate the arrangement of stationary switch contacts;

Figures '7. 'ie and 7b are somewhat diagrammatical sectional views takenalong the line 1--i of Figure and showing the manner in which the switchis operated;

Figures 8 and 9 are views similar to Figures 2 and 3 but showingswitch-open and switch closed positions respectively in a slightlymod-ified form of the switch; and

Figure 10 is a cross sectional view taken through Figure 7 along theplane of the line Ill-l3.

Referring now more particularly to the accompanying drawings in whichlike numerals indicate like parts, and especially to that form of theinvention illustrated in Figures 1 to 6, inclusive, the numerals 5 and'6 designate the switch and rheostat components respectively of acombined switch and volume control instrumentality such as isparticularly suited for use with small radio receivers, and especiallyautoinob'ile receivers. Both the switch and the volume control areoperated by a common shaft 1.

The housing means for the combined instruinentality includes from andback walls 9 and {lo respectively and intermediate wall ii 's'p'a'cedsubsta'i'i'tially midway between the front and back walls and which actsas a partition wall to separate the housing means into a front housing"section i2 in which the volume control mechanism (not shown) isreceived, and a rear housing section [3 in which the switch mechanisinof this invention is contained. Actually the housing means is comprisedof two cupshaped casings, one for the volume control and one for theswitch mechanism, with the open end of the switch housing abutting thepartition wan H pro sided by the bottom of the volume control housl 1g,so that the switch is earned on the back or the volume control. some theside waits or the two housing section's substantially align, they form,in effect, a continuous cylindrical wall enclosing the two instruments.

The manner in which the rear housing section is secured to the fronthousing section is more or less conventional in that it comprises aplurality or" ears is projecting forwardly iron- 'tlie side wall I? atthe open end of the switch housing and passing through perforations inthe back wall ll of the volume control housing, the ears :5 being turnedover against the 'front 'face of the wall Ii to secure the switchhousing to the volume control housing with the run at the open end ofthe switch housing tightly engaged against the backside of the wall II.

This manner of connecting the two housing sections together mechanicallyalso serves to connect them electrically; while the partition wall llacts as an electrical shield between the volume control and switchmechanisms.

As is customary in 'instrumentalities of nature the operating shaft isrotatably carried by the front wall 9 of the housing means and projectscoaxially therethrough into the interior of the front housing sectioncontaining the volume control mechanism to operate the same. As willappear in greater detail hereinafter, the inner end of the operatingshaft terminates short of the partition wall I l and has a driver 19fixed thereto for operating the switch mechanism.

The end wall [0 provided by the bottom of the switch casing or rearhousing section comprises a fiat disc of insulating material and servesas the terminal head of the switch. It is fixed in position on theswitch casing by being confined between a flange 2i, turned inwardlyfrom the rear end of the side wall I! of the switch casing, and a seriesof indentations 22 in the side wall in line with the ears [6 and whichoverlie the inner or front face of the terminal head. Anotherindentation 23 in the side wall at its extr'eine rear enters a notch 24in the edge of the terminal head to hold the same against rotation.

At its open end, which is closed by the partition wall H upon attachmentof the switch casing to the back of the volume control housing, the sidewall I! of the switch casing is indented outwardly to provide opposedsockets 2% which open inwardly toward one another along a line extendingacross the switch housing a short distance to one side of the center ofthe housing. These sockets are more or less V-shaped and their apexesextend longitudinally from the ex treme front or rim of the side wallI'I rearwardly to a point )intermediate the rim and terminal head It;and at these points the indentat'ions are sheared from the side wall toprovide shoulders or abutments 21 on the side wall facing the open endof the switch casing and radially inwardly of the apexes of the V-shaped notches.

These sockets or notches 26 pivotally receive the opposite ends of aspring actuating blade 29 to hold the blade edgewise with respect to theterminal head Ill and in a position extending transversely across theswitch housing. At the ends of the blade, its bottom edge 3E3 seats onthe shoulders 21 at the inner ends of the sockets to hold the bladespaced from the terminal head.

The partition wall H afiorded by the back of the volume control housingextends across the outer ends of the sockets to overlie the upper edges31 of the extremities of the spring blade to thus cooperate with theshoulders 2'! in maintaining the blade in its proper position in theswitch housing.

The bottoms of the sockets 26 in which the extremities of the blade seatare spaced apart from one another a distance less than the length of thespring blade so that the blade is yieldingly held with its intermediateportion bowed flatwise to one side or the other and 'away from thestraight line which joins the apexes of the sockrats, as seen in Figures2 and 3. The resiliency of the blade, however, allows the intermediateportion thereof to be deflected out of either bowed attitude toward theline joining the apexes of the sockets 'a'ndbeyond a critical positionadjacent to said line from which the intermediate portion of the springblade snaps to its oppositely bowed position. v

In Figure 2 the intermediate portion of the blade is shown bowedoutwardly away from the the center of the switch casing and the linejoining the apexes of the sockets. When force is applied to theintermediate portion of the blade to move the same inwardly, tending tostraighten the blade, it passes a critical position close to the linejoining the apex'es of the sockets at which the force built up in theblade is suddenly released, causing the intermediate portion of theblade to snap to its oppositely bowed attitude, toward the center of theswitch casing as seen in Figure 3.

The same snap action takes place 'upon the .1 application of radiallyoutward force to the intermediate portion of the blade to reverse itsbowed position shown in Figure 3 and return it to the bowed positionseen in Figure 2.

Motion is imparted to the intermediate portion of the spring blade tocarry it beyond its critical position from either of its bowed attitudesby the driver I 9 on the inner end of the operating shaft 7. For thispurpose the spring blade has an extension 33 on its front side edgewhich projects through an aperture 33' in the partition wall H,elongated in the direction of the length of the spring blade, with theextension projecting into the interior of the volume control housingadjacent to the driver [9.

Driving lugs 34 and 35 on the driver, projecting rearwardly therefrom,provide for moving the intermediate portion of the blade from either ofits bowed attitudes toward and beyond the critical position at which. itsnaps to the opposite bowed attitude. These driving lugs are spacedcircumferentially, and the lug 34 travels in an orbital path locatedfarther from the axis ofrotation of the operating shaft than that of thelug 35. The actuating blade 29 is so mounted relative to the paths oftravel of the lugs 34 and 35 that the extension 33 on the blade lies inthe path of the lug 35 in either bowed attitude of the blade, while theextension 33 is moved into and out of the path of travel of the lug 34when the blade is snapped respectively to and from its outwardly bowedposition seen in Figures 2 and '7. Consequently during rotation of theshaft, the lug 34 passes radially outwardly of the extension 33 to clearthe same when the intermediate portion of the blade is bowed inwardlytoward the center of the switch housing, as seen in Figures 3 and '71).

When the blade 29 is in its inwardly bowed attitude (Figures 3 and 7b)the lug 35 is brought into engagement with the extension 33 bycounterclockwise rotation of the shaft to flex the intermediate portionof the actuating blade outwardly toward the line joining the apexes ofthe blade sockets and beyond the critical position adjacent to said lineat which it snaps away from the lug 35 to its outwardly bowed attitudeseen in Figures 2 and 7. I

Such counterclockwise rotation of the operating shaft, of course, islimited to preclude reengagement of the driving lug 35 with theextension 33 after the blade has snapped to its Figures 2 and 7positions, and this is accomplished by the engagement of a stop lug 3'!on the driver with one side of a stop 38 provided by an indentation inthe rear portion of the volume control housing. At the time of suchengagement of the stops, the driving lugs 34 and 35 lie on oppositesides of the extension 33 on the spring blade, with the lug 34 adjacentto the outer convex face of the blade and in position to be brought intoengagement with the extension 33 by clockwise rotation of the operatingshaft bring the lugs to a position seen in Figure '7.

Consequently, clockwise rotation of the operating shaft from theposition shown in Figure 7 will cause the intermediate portion of theblade to be flexed inwardly toward the center of the switch housing bythe lug 34, and the intermediate portion of the blade will snap to itsinwardly bowed position seen in Figures 3 and 7a after it passes acritical position adjacent to the line joining the apexes of the bladesockets. In Figures 3 and 7b the extension 33 on the blade has beencarried to a position inside the path of movement of the driving lug 34to allow further clockwise rotation of the operating shaft for volumecontrolling purposes. The stop 38, of course, allows nearly fullrotation of the shaft and stop clockwise rotation thereof when itsopposite side is engaged by the stop lug 37 on the driver.

This back and forth snap action of the spring blade 29 between itsoppositely bowed attitudes is utilized to snap the contact carrier 43 ofthe switch back and forth between switch-open and switch-closedpositions in a manner now about to be described.

The contact carrier 40 is a fiat disc of insulating material and has asomewhat hexagonal shape. It is loosely received in the bottom portionof the switch casing in the space between the terminal head and the rearedge of the switch actuating blade 29. Slightly oif its center, thecarrier is provided with a rectangular hole 42, elongated in thedirection of the length of the actuating blade, and into which a lug ordriver 43 on the rear edge of the blade loosely projects to provide amotion transmitting connection between the blade and the contact carrierlocated medially of the ends of the blade. The dimensions of the hole 42with respect to the driver 43 are such that there is only enoughclearance between the opposite ends of the hole and the adjacent sideedges of the driver as to afford a degree of edgewise rotational motionof the contact carrier about the driver, while substantially precludingback and forth edgewise motion of the carrier in the direction of thelength of the actuating blade. For this reason also there is clearancebetween the long side edges of the hole 42 and the opposite side facesof the driver.

Hence, it will be apparent that as the intermediate portion of the bladesnaps back and forth between its oppositely bowed attitudes seen inFigures 2 and 3 it will snap the contact carrier along with it; whilethe back and forth motion imparted to the contact carrier by the bladeis substantially a translating motion crosswise of the length of theactuating blade.

The carrier 40 has a pair of elongated movable contact members 45connected therewith to be carried thereby into and out of bridgingengagement with pairs of stationary contacts 46 mounted on the terminalhead Ill. The contact members 45 are confined in the space between theunderside of the contact carrier and the inner face of the terminal headand each has a pad 43 on its medial portion which slidingly engages theinner face of the terminal head to localize the contact therewith.

The contact members are connected with the carrier to be located atopposite sides of the driving connection between the blade and thecarrier, with the contact members extending lengthwise in the directionof switch-opening and switch-closing motion of the carrier. Theconnections between each contact member and the carrier includes a tail53 bent forwardly from one end of the contact member, away from theterminal head, and loosely received in an aperture 5! in the carrieradjacent to the outer side of the actuating blade 29, so that theopposite end of the contact member may swing about the pivot provided bythe tail 53, back and forth across the underside of the contact carriersubstantially in the direction of the length of the spring blade 29.

Such pivotal motion of the contact members is limited, however, sinceeach has a for- "weirdly bent neck 52 on its outer extremity projectingloosely through a hole 53 in the carrier. On their outer ,orforw-ardzends, eachof the necks 52 has ahead :54 formed thereon, andthese heads have a length greater than the width of the aperture :53 sothat they overlie the front face of the contact carrier.

It will be understood, of course, that the holes 53 have a length suchthat the .heads 54 may pass therethrough when the contact members areassembled with the carrier, which assembly is enacted by holding thecontact members .in a position displaced 90 from their assembledpositions.

The intermediate portion-of each contactmomber surrounding its pad 48 isenlarged as at 56,. and these enlargements provide the bridging portionsof the contact members which en age between the bridge the stationarycontacts -46 of the switch. As seen best in Figures 4 and 6 the bridgingportions '55 are more or less round, while the portions of thestationary contacts bridged thereby are at an anglesuch as to provide awedging action of the movable contacts between stationary contacts asthe switch is closed.

With the construction described, it will be apparent that not only arethe movable contacts 45 'pivotable about their trunnion forming ends 6and consequently self-aligning with respect to their cooperatingstationary contacts, but the carrier itself is also capable of a degreeof edgewise pivotal motion about the driver :43 to onhomes thisself-centering feature. Also, since the driver on the actuating bladeengage the contact carrier at a point substantially midway between theareas of engagement between the mobable contacts 45 and their stationarycontacts, the force of the actuating blade holding :the stationarycontacts bridged is substantially equally divided between each set ofmovable and stationary contacts.

The stationary contacts 46 are on the order of those shown and:described in Patent 'No. 2,529,716 issued to Adrian J. Vaksvik andMervin .B. Arisman November 14, 1950, and comprise the inner ends .ofthe terminal posts 58 of the switch. These combined terminal posts andstationary contacts are stamped from flat stock and project throughslits the terminal head to have their terminal portions exposed at theback of the switch casing, being secured to the terminal head by swedgedportions '55 which engage the rear orouter face of the terminal-head anddraw lateral extensions on the contact portions of the posts into firmengagement with the inner face or the terminal head.

In the present case also the inner ends -60 which provide the contactportions of the posts .alllie in a common plane spaced from but parallelto the inner face of the terminal head and provide supporting surfaceswith which the underside of the contact carrier engages. The contactcarrier '40 is loosely held on the supporting surf-aces provided by thestationary contacts by means of a relatively small foot 61 on the rearedge of the actuating blade 29, projecting therefrom directly alongsidethe driver 43.

'It will be noted also that the foot 61 has the additional function ofholding the rear edge of the actuating blade spaced from the adjacentouter faceof the contact carrier for substantially the entire length ofthe blade.

@ne of the limits of back and forth motion of the contact carrier, ofcourse, is defined "by the nga ment or its movable contacts with theircooperating stationary contacts, as shown Figure .3. The other limit ofmotion, .or more particularly the switch-open position of the carrier,is defined by the engagement of one straight flige 63 thereof with theadjacent indented portion 22 of the switch casing, along with theengagement of opposite convex edges .64 of the carrier near .the ends ofthe actuating blade 28 with the side wall of the switch housing.

.As a result the contact carrier and the contactors thereon have .a[relatively long straight line travel despite the small size of thehousing, and this is important since it determines the distance betweeneach pair of stationary contacts'and-itsbridghigcontactor.

The transletory or straight line motion of the contact carrier and the.fact that the-contactsun faces of the stationary contacts are solocatedthat a straight normal to the path of travel of the contact carrierintersects all these contact surfaces assures maximum electricalclearance between the contacts and the :contactors when the switchisopen. In other words, by virtue 0f the disposition of the stationarycontacts in arow normal to the plane contacting the axis of the housingand the connection 42 between the contact carrier and the Spring blade29, both oontactors move away from all of the stationary contacts as thecontact carrier travels toward its switch open position.

One of the most important vfeatures of the switch mechanismdescribedisthat the extension .33 of the actuating blade, with which the drivinglugs 34 and on the operating shaft transiently engage, is locatedsubstantially midway between one of the pivoted :ends of the blade andthe point at which the blade is drivingly connected with the contactcarrier. This enables the intermediate portion of the blade to be flexedbeyond the snap over point without imparting motion to the contactcarrier, with the result that uniform contact pressure is maintained inthe switch-closed position right up untilithe time the intermediateportion of the blade snaps to its outwardly bowed position to open theswitch.

The snap switch illustrated .in Figures 8, 9 and 10 embodies the sameprinciples of the .switch shown in Figures 1 .to -71) inclusive, anddiffers therefrom chiefly in the construction of the contact carrier 40:and the manner of connecting the movable contacts :68 therewith. Inthis case also the stationary contacts it are located substantially inthe same positions as the contacts 16 in the previous embodiment.

The switch blade 29 "however has its ends pivotally received in socketswhich hold the blade at the opposite side of the center of the switch.housing, i. e. above the center rather than below with relation toFigure 2; although it snaps the contact carrier in "the samedirection-(upwardly) to effect closure of the switch as it does in theFigure 2 embodiment.

The main feature of this modified switch resides in the 'fact that thecontact engaging portionsof the stationarycontacts have forwardextensions b8 thereon which loosely project through slots 69 in thecarrier-elongated in the direction of its switch-opening and closingmotion to guide the carrier for such motion.

The movable contacts 66 are also of simpler design, being stamped andbent flatwise to substantially U-shape. The legs of the U-shapcd movablecontacts diverge slightly toward their outer ends, and are confinededgewise between 9 the underside of the carrier and the inner face ofthe terminal head.

At their closed end portions, each of the U-shaped movable contacts hasan extension it which projects edgewise forwardly through an opening inthe contact carrier and is engaged over the rounded outer end of atongue 1! formed on the carrier to enable rocking of the movablecontacts about the extremities of the tongues. Since the extensions Iiiextend part way along the diverging ends of the legs of the contacts tolie opposite the side edges of the tongues ll, rocking movement of thecontacts on their tongues is limited; while motion of the movablecontacts off of the rounded ends of their tongues or pivot posts islimited by the engagement of the closed ends of the U-shaped contactswith abutments 12 on the carrier opposite the rounded extremities of thetongues and spaced therefrom a distance slightly greater than thethickness of the movable contacts.

Although the same desirable advantage of equalized and adequate contactpressure between the movable contacts and their stationary contacts issecured by this arrangement, it will be noted that the point at whichthe actuating blade is drivingly connected with the contact carrierleads the bridging portions of the movable contacts duringswitch-closing motion, while in the previous embodiment this point ofconnection trailed the enlarged bridging portions 56 of the movablecontacts.

Also by reason of the disposition of the actuating blade 29', the bladesprings to an outwardly bowed attitude to effect closure of the switch,and to an inwardly bowed attitude to effect opening of the switch.

Another feature of the switch shown in Fig ures 8, 9 and 10 is that .theblade 29' has tongues M on its opposite ends which project beyond theextremities of the blade along the rear edge thereof and pass throughopenings in the side wall of the switch housing to anchor the bladeagainst edgewise motion forwardly, or away from the bottom wall of theswitch housing. Consequently, the blade 29' will be positively heldagainst disassembly from the switch housing prior to attachment of theswitch housing to the back of the volume control housing.

From the foregoing description, together with g the accompanyingdrawings, it will be apparent to those skilled provides an improveddouble pole single throw snap switch, which though simplified in designby the suspension of the contact carrier from the actuating blade toeliminate pivot posts and the like for mounting the contact carrier,achieves such outstanding advantages as self-aligning of the movablecontacts with respect to their stationary contacts, and equal divisionof contact pressure between the two sets of movable and stationarycontacts.

What I claim as my invention is:

1. In an electrical control instrumentality of the character described:a substantially cupshaped switch housing including a side wall and abottom Wall at one end of the switch housing; stationary contactssecured to said bottom wall; a substantially flat insulative contactcarrier inside the bottom portion of the switch housing fiatwiseoverlying the bottom wall of the housing and movable edgewise to andfrom switch-open and switch-closed positions; supporting means on saidbottom wall for spacing the contact carrier therefrom and upon which thecontact carrier in the art that this inventioniii slides duringswitch-opening and switch-closing movement; means on the side wall ofthe switch housing providing opposed sockets which open toward oneanother and to the outer edge of the housing side wall; a shoulder ineach of said sockets spaced from the open end of the switch housing butfacing the same; a cover engaged over the open end of the switch housingto close the same, said cover having an opening therein; an actuatingblade for snapping said contact carrier to and from switch-open andswitchclosed positions, said blade having its opposite ends pivotallyreceived in said sockets and confined therein between said shoulders andthe cover, said blade extending edgewise across the contact carrierbetween it and said cover; a motion transmitting connection between theintermediate portion of the spring' blade and the contact carrier; afoot on the edge of the blade adjacent to the contact carrier andengaged therewith to cooperate with said supporting means for thecontact carrier to substantially preclude flatwise motion of the contactcarrier in the switch housing; and an extension on the opposite edge ofthe spring blade projecting through said opening in the cover to enablethe switch actuating blade to be operated from outside the switchhousing.

2. In a snap switch: a substantially cupshaped switch housing havingstationary contacts exposed on the inner face of its bottom wall; asubstantially flat insulative contact carrier loosely received in thebottom portion of said housing and movable edgewise in a planesubstantially parallel to the bottom wall of the housing to and frompositions carrying contact means thereon into and out of engagement withsaid stationary contacts; supporting means on the bottom wall of thehousing engaging the underside of the carrier to guide the carrier foredgewise motion parallel to the bottom wall of the housing; a springblade extending edgewise across the outer side of the carrier andcrosswise of the direction of switch-opening and closing motion of thecarrier; connections between the opposite ends of the spring blade andthe side wall of the housing so spaced from one another with respect tothe length of the blade as to impose a force on the blade tending tohold its intermediate portion bowed to one side or the other and awayfrom a straight line joining the extremities of the blade so that theintermediate portion of the blade snaps from one bowed attitude to theother upon being deflected toward said line and beyond a criticalposition adjacent thereto; a motion transmitting connection between theintermediate portion of said blade and the contact carrier whereby thelatter is snapped to switch-open and switch-closed positions inconsequence to reversal of the bowed attitude of the blade; and a footon the medial portion of the blade engaged with the outer side of thecontact carrier to hold the major length of the blade spaced from thecarrier, said foot cooperating with said supporting means on the bottomwall of the housing to constrain the contact carrier to edgewise motionparallel to said bottom wall of the housing.

3. In a snap switch: a switch casing including a substantially tubularside wall, and a terminal head extending across and closing one end ofsaid tubular side wall; a substantially flat con tact carrier looselyreceived in said casing and fiatwise overlying the inner side of theterminal head; a spring blade connected at its opposite ends with theside wall of the casing to lie edgewise adjacent to the outer side ofsaid contact carrier and extending thereacross, the intermediate portionof said spring blade being normally bowed fiatwise to one side or theother of a straight line joining its opposite extremities but beingmovable back and forth between said bowed positions with a snap action;a driving lug on the medial portion of said blade received in anaperture in the contact carrier so that the carrier is snapped back andforth between switch-open and switch-closed positions in consequence toreversal of the bowed attitude of the blade, said connection between theblade and the carrier affording limited edgewise turning motion of thecarrier about said driving lug; a pair of contacts on said carrier, oneat each side of its driving connection with the blade; and cooperatingstationary contacts on the terminal head bridged by said contacts whenthe carrier is snapped in one direction by the blade, the location ofthe contacts on the carrier at each side of its driving connection withthe blade and the limited turning motion of the carrier with respect tothe blade providing for. selfalignment of the carrier contacts withrespect to their cooperating stationary contacts.

4. The switch set forth in claim 3 further characterized by theprovision of connections between the contact. carrier and its contactswhich provide said contacts with a limited degree of motion relative tothe carrier in the direction of the length of the spring blade tofurther facilitate centeringof the movable contacts with theircooperating stationary contacts.

5'. In a snap switch: a switch housing having a hat bottom wall and acylindrical side wall pivot forming means on opposite portions of thehousing side wall, said pivot forming means being so located that thedistance therebctween is less than the diameter of the housing and aline connecting them lies chordwise' to one side of the center of thehousing; a spring blade having its opposite ends connected to said pivotformingmeans and extending; across the housing edgewise with respect tothe bottom wall of the housing and spaced therefrom, said blade beinglonger than the distance between the" pivot formingmeans so that theblade is always bowed to one side or the other of a straight linejoining the pivot forming means and its intermediate portion isdeflectible out or" either bowed attitude toward said line and beyond. acritical, position adjacent to said line from which it snaps to itsoppositely bowed attitude; a substantially flat disc-like contactcarrier loosely received in the bottom portion of the housing andconfined flatwise between the bottom wall of the housing and theadjacent edge of the spring blade; a motion transmitting connectionbetween the contact car-- rier and said intermediate portion of theblade whereby the carrier is snapped back and forth between switch onand switch off positions with an edgewise translating motion along apath atright angles to a straight line joining the pivot forming meansin consequence of reversal of the bowed attitude of the blade, saidmotion transmitting connection being so located on the com tact carrierthat when the blade is bowed away from the center of. the housing theleading edge of the contact carrier comes to bear against the side wallof the housing; and cooperating contacts on the contact carrier and thebottom wall of the housing.

6. In a snap switch: a switch housing having a 12 side wall and a bottomwall closing one end: of the housing; spaced apart stationary contactson the inner side of said bottom wall; a spring blade connected at itsopposite ends to the housing side wall to extend across the switchhousing edgewhe to said bottom wall but spaced therefrom, saidconnections imposing a force on the blade tending to hold itsintermediate portion bowed to one side or the other and away from astraight line joining theextremities of the blade, and said intermediateportion of the blade being defiectiblc out of either bowed attitudetoward said line and beyond a critical position adjacent thereto fromwhich it snaps to its oppositely bowed attitude; fiat supportingsurfaces on said stationary contacts' lying in a common planeintermediate said spring blade and the bottom wall of the housing; amovable substantially flat contact carrier loosely received in theswitch housing and flat confined between said supporting surfaces on thestationary contacts and said spring blade to be constrained thereby toedgewise motion on said supporting surfaces; a driving connectionbetween said contact carrier and the spring blade at a point on theblade substantially medially of its. ends, whereby the carrier issuspended from the blade to be snapped back and forth by the blade inconsequence of reversal of the bowed attitude thereof and in a directioncrosswise. oi the length of the blade, to carry contact means on thecarrier into and out of bridging engagement. with the stationarycontacts, said driving connection allowing a. degree of relative pivotalmovement between the contact. carrier and the spring blade; and.cooperating means. on said, stationary contacts and the contact. carrierguiding the carrier for substantially straight line back and forth.motion with the spring blade '7. The snap switch set forth in claim 6wherein said cooperating means which guides the contact carrier for backand forth motion comprises spaced parallel slots in the carrierextending lengthwise in the. direction of back. and forth. motion of thecarrier, and extensions on the stationary contacts projecting throughsaid slots and loosely fitting the same.

8. The snap switch of claim '1 further charac terized by the fact thatthe. portion of the contact carrier which lies between the stationarycontacts when the same are bridged is cut. out to provide a pivot postfacing in. the direction in: which the carrier travelsto effect bridgingof the stationary contacts; and a substantially U-shaped movable contactconfined between the carrier and the bottom Wall. of theswitch housingand. havingv an extension. at its closed end projecting through saidout. out portion of the carrier and seating on the extremity of saidpivot post,,where.- by the movable contact. is tiltably connected withthe carrier and is self-aligning with respect tosaid stationarycontacts.

9. In a snap switch-z. a. switch housing having a. side wall, and. abottom wall closing one end of the housing; a spring blade; in said.housing extending thereacross cdgewise. with respect. to said bot-tomwall and spaced therefrom; connections between the opposite endsof thespring blade and the housing side Wall. holding the: blade with its.intermediate portion. bowed to one side;- or the other and away from astraight line passing through said connections, the intermediate por'tion of the blade. being, deflectible. out. of either.v bowed attitudetoward; said line and beyondv a.-

criti'cal position adjacent. thereto from which. it snaps to itsoppositely bowed attitude; a substantially flat contact carrier looselyreceived in said housing and flatwise overlyin the bottom wall thereof,in said space between the bottom wall of the housing and the adjacentedge of the spring blade, so as to be constrained to edgewise movementin the housing; a motion transmitting connection between the contactcarrier and said spring blade at a point on the latter substantiallymedially of its ends, said motion transmitting connection substantiallysuspending the carrier from the blade and constraining the carrier toedgewise substantially translatory back and forth motion with the medialportion of the blade so that the carrier may be snapped back and forth.between switch on and switch off positions in consequence of reversal ofthe bowed attitude of the blade; and an integral extension on the edgeof the blade remote from the contact carrier, substantially mediallybetween one end of the blade and its connection with the carrier toenable switch operating force to be applied directly to the blade at adistance from its connection with the carrier.

10. The snap switch set forth in claim 9 wherein said connectionsbetween the opposite ends of the spring blade and the housing side wallcomprise outwardly pressed portions on the side wall providing V-shapedsockets in which the extremities of the spring blade are pivotallyreceived, and tongues on the ends of the blade extending beyond itsextremities and through openings in the side wall of the switch housingto hold the blade against edgewise motion away from the bottom wall ofthe housing.

11. A double pole, single throw switch of the character described,comprising: a housing having a cylindrical side wall and a flat bottomwall; two pairs of stationary contacts on the inner face of the bottomwall electrically insulated from one another, said two pairs ofstationary contacts being disposed symmetrically at opposite sides of aplane perpendicular to the bottom wall and containing the axis of thehousing and having opposing contact surfaces spaced apart along astraight line normal to said plane; a movable contact carrier overlyingthe inner face of the bottom wall; means for driving the contact carrieracross the bottom wall of the housing between switch closed and switchopen position and with a substantially translatory motion along a pathparallel to said plane, said means being connected to the carrier onsaid plane and including a spring reacting between the side Wall of thehousing and the carrier for urging the carrier toward it switch closedposition; and, a pair of contactors mounted on the carrier and spacedequidistances from said plane and from one another on a line normal tosaid plane with the distance between said contactors corresponding tothe center-to-center distance between the two pairs of stationarycontacts so that said contactors move into bridging engagement withtheir respective stationary contacts as the carrier assumes its switchclosed position and move away from all of the stationary contacts as thecarrier moves toward its switch open position.

12. The switch of claim 11 further characterized by the fact that theconnection between the driving means and the movable contact carrier andalso the connections between the contactors and the carrier have limitedpivotal freedom about axes perpendicular to the bottom wall of thehousing so that the contactors are self aligning as they are driven intobridging engagement with their respective stationary contacts.

13. The switch of claim 11 wherein the means for driving the carrieracross the bottom wall of the housing between switch closed and switchopen position comprises: a spring blade having its ends rockablysupported on opposite portions of the housing side wall so located thata straight line joining the ends of the blade is normal to said planeand extends chordwise across the bottom wall of the housing between thestationary contacts and the side of the housing toward which the contactcarrier moves in travelling toward its switch open position, said springblade being disposed edgewise with respect to the bottom wall of thehousing and lying above the contact carrier and being longer than thedistance between the opposite portion of the side wall upon which itsends are supported so that the blade is always bowed to one side or theother of said straight line, and its intermediate portion is defiectibleout of either bowed attitude toward said line and beyond a criticalposition adjacent to said line from which it snaps to its oppositelybowed attitude; and a connection between the blade and the movablecontact carrier, said conn ction being located medially of the ends ofthe blade.

14. The switch of claim 13 further characterized by the provision of anintegral extension on the edge of the blade remote from the contactcarrier, substantially medially between one end of the blade and itsconnection with the carrier to enable switch operating force to beapplied directly to the blade a distance from its connection with thecarrier.

15. A double pole, single throw switch of the character described,comprising: a housing having a cylindrical side wall and a fiat bottomwall of insulating material; two pairs of stationary contacts mounted onsaid bottom wall and disposed symmetrically at opposite sides of a planeperpendicular to the bottom wall and having contact surfaces spacedalong a straight line normal to said plane; a flat substantiallydisc-like contact carrier slidable edgewise across the tops of thestationary contacts; means constraining the contact carrier tosubstantially translatory motion along a path parallel to said plane; apair of contactors mounted on said contact carrier for coaction with thestationary contacts, said contactors being equispaced from said planeand spaced from one another on a line normal to said plane with thedistance between the contactors corresponding to the center-to-centerdistance between the pairs of stationary contacts so that saidcontactors move into bridging engagement with their respectivestationary contacts as the carrier assumes its switch closed positionand move away from all of the stationary contacts as the carrier movestoward its switch open position; and means for sliding the contactcarrier between its switch closed and switch open positions, including aspring biasing the contact carrier in a direction to hold the contactorsin bridging engagement with the stationary contacts in the switch closedposition of the contact carrier.

16. The electric switch of claim 15, further characterized by the factthat: the portion of the contact carrier which lies between thestationary contacts when the carrier is in its switch closed positionhas an opening therein one edge of which is shaped to provide a pivotpost facing in the direction in which the carrier travels in movingtoward its switch closed position; and by the fact that; thew movablecrmtactox; is substantial-1 ushaped, and confined fia-twise; between-Lthe; camnier' and; the. base and: has extension; on; its bi'ghtprojecting into said opening in the carrier and embracing the extremityof said pivot post, whereby the movable contactor i's til tablyconnectedthe carrier and is self aligning with respect to the stationarycontacts.

J. VAKSVIK.

Numb

N Dat Mitchell May 4, 1926 Thomas Oct. 22, 1929- S ommermeyer Esept. '71937 Sqhellenger Oct. 25', 1939 Q0 4 1----- -.-v-A-- Apr. 40 SchellengerAug 1 3', 1940 USH?! 4 Ju y 6,

F anks at 53 c -1 1 50.

